Download - Binoculars or binocular telescopes
Binocular telescopes or binoculars (also known as field glasses), are two identical or mirror-symmetrical telescopes mounted side-by-side and aligned to point accurately in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects.
GALI LEAN TELESCOPE Found in 17th century Mounting two telescopes side by side for binocular
vision Convex objective & concave eyepiece lens
.
PORRO PRISM BINOCULARS Found by Ignazio porro in 1854 Improved image & higher magnification They are used in keplerian telescopes The disadvantage of keplerian telescope is inverted
images are formed Two prisms are used
Z -SHAPE CONFIGURA
TION
Found in 1870 Purpose is to erect the image Objective lens in line with the eye piece
MAGNIFICATION Ratio of focal length of eyepiece & focal length of
the object gives the linear magnification OBJECTIVE DIAMETER Diameter of the objective lens determines how much
amount light can be gathered to form a image Expressed in millimeters FILED OF VIEW Field of view is determined by the optical design Notated in angular value as how many degrees can
be viewed
General use - hand held binoculars Military use - naval ship binoculars Astronomical – for viewing
planets ,comets and supernova seeking
GENERAL BINOCULAR TELESCOPE
ASTRONOMICAL BINOCULARTELESCOPE
NAVAL SHIP BINOCULAR TELESCOPES
- THANKYOU- PRESENTED BY- MOHAN KUMAR
- A student of shri prakash institute of optometry-DR.AGARWALS EYE
HOSPITAL (Chennai, Tamilnadu)